llvm-project/clang/lib/ARCMigrate/Transforms.cpp

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//===--- Tranforms.cpp - Tranformations to ARC mode -----------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// Transformations:
//===----------------------------------------------------------------------===//
//
// castNonObjCToObjC:
//
// A cast of non-objc pointer to an objc one is checked. If the non-objc pointer
// is from a file-level variable, objc_unretainedObject function is used to
// convert it.
//
// NSString *str = (NSString *)kUTTypePlainText;
// str = b ? kUTTypeRTF : kUTTypePlainText;
// ---->
// NSString *str = objc_unretainedObject(kUTTypePlainText);
// str = objc_unretainedObject(b ? kUTTypeRTF : kUTTypePlainText);
//
// For a C pointer to ObjC, objc_unretainedPointer is used.
//
// void *vp = str; // NSString*
// ---->
// void *vp = (void*)objc_unretainedPointer(str);
//
//===----------------------------------------------------------------------===//
//
// rewriteAllocCopyWithZone:
//
// Calls to +allocWithZone/-copyWithZone/-mutableCopyWithZone are changed to
// +alloc/-copy/-mutableCopy if we can safely remove the given parameter.
//
// Foo *foo1 = [[Foo allocWithZone:[self zone]] init];
// ---->
// Foo *foo1 = [[Foo alloc] init];
//
//===----------------------------------------------------------------------===//
//
// rewriteAutoreleasePool:
//
// Calls to NSAutoreleasePools will be rewritten as an @autorelease scope.
//
// NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
// ...
// [pool release];
// ---->
// @autorelease {
// ...
// }
//
// An NSAutoreleasePool will not be touched if:
// - There is not a corresponding -release/-drain in the same scope
// - Not all references of the NSAutoreleasePool variable can be removed
// - There is a variable that is declared inside the intended @autorelease scope
// which is also used outside it.
//
//===----------------------------------------------------------------------===//
//
// makeAssignARCSafe:
//
// Add '__strong' where appropriate.
//
// for (id x in collection) {
// x = 0;
// }
// ---->
// for (__strong id x in collection) {
// x = 0;
// }
//
//===----------------------------------------------------------------------===//
//
// removeRetainReleaseDealloc:
//
// Removes retain/release/autorelease/dealloc messages.
//
// return [[foo retain] autorelease];
// ---->
// return foo;
//
//===----------------------------------------------------------------------===//
//
// removeEmptyStatements:
//
// Removes empty statements that are leftovers from previous transformations.
// e.g for
//
// [x retain];
//
// removeRetainReleaseDealloc will leave an empty ";" that removeEmptyStatements
// will remove.
//
//===----------------------------------------------------------------------===//
//
// changeIvarsOfAssignProperties:
//
// If a property is synthesized with 'assign' attribute and the user didn't
// set a lifetime attribute, change the property to 'weak' or add
// __unsafe_unretained if the ARC runtime is not available.
//
// @interface Foo : NSObject {
// NSObject *x;
// }
// @property (assign) id x;
// @end
// ---->
// @interface Foo : NSObject {
// NSObject *__weak x;
// }
// @property (weak) id x;
// @end
//
//===----------------------------------------------------------------------===//
//
// rewriteUnusedDelegateInit:
//
// Rewrites an unused result of calling a delegate initialization, to assigning
// the result to self.
// e.g
// [self init];
// ---->
// self = [self init];
//
//===----------------------------------------------------------------------===//
//
// rewriteBlockObjCVariable:
//
// Adding __block to an obj-c variable could be either because the the variable
// is used for output storage or the user wanted to break a retain cycle.
// This transformation checks whether a reference of the variable for the block
// is actually needed (it is assigned to or its address is taken) or not.
// If the reference is not needed it will assume __block was added to break a
// cycle so it will remove '__block' and add __weak/__unsafe_unretained.
// e.g
//
// __block Foo *x;
// bar(^ { [x cake]; });
// ---->
// __weak Foo *x;
// bar(^ { [x cake]; });
//
//===----------------------------------------------------------------------===//
//
// removeZeroOutIvarsInDealloc:
//
// Removes zero'ing out "strong" @synthesized properties in a -dealloc method.
//
//===----------------------------------------------------------------------===//
#include "Internals.h"
#include "clang/Sema/SemaDiagnostic.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/AST/StmtVisitor.h"
#include "clang/AST/ParentMap.h"
#include "clang/Analysis/DomainSpecific/CocoaConventions.h"
#include "clang/Lex/Lexer.h"
#include "clang/Basic/SourceManager.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/DenseSet.h"
#include <map>
using namespace clang;
using namespace arcmt;
using llvm::StringRef;
//===----------------------------------------------------------------------===//
// Transformations.
//===----------------------------------------------------------------------===//
namespace {
class RemovablesCollector : public RecursiveASTVisitor<RemovablesCollector> {
llvm::DenseSet<Expr *> &Removables;
public:
RemovablesCollector(llvm::DenseSet<Expr *> &removables)
: Removables(removables) { }
bool shouldWalkTypesOfTypeLocs() const { return false; }
bool TraverseStmtExpr(StmtExpr *E) {
CompoundStmt *S = E->getSubStmt();
for (CompoundStmt::body_iterator
I = S->body_begin(), E = S->body_end(); I != E; ++I) {
if (I != E - 1)
mark(*I);
TraverseStmt(*I);
}
return true;
}
bool VisitCompoundStmt(CompoundStmt *S) {
for (CompoundStmt::body_iterator
I = S->body_begin(), E = S->body_end(); I != E; ++I)
mark(*I);
return true;
}
bool VisitIfStmt(IfStmt *S) {
mark(S->getThen());
mark(S->getElse());
return true;
}
bool VisitWhileStmt(WhileStmt *S) {
mark(S->getBody());
return true;
}
bool VisitDoStmt(DoStmt *S) {
mark(S->getBody());
return true;
}
bool VisitForStmt(ForStmt *S) {
mark(S->getInit());
mark(S->getInc());
mark(S->getBody());
return true;
}
private:
void mark(Stmt *S) {
if (!S) return;
if (LabelStmt *Label = dyn_cast<LabelStmt>(S))
return mark(Label->getSubStmt());
if (ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(S))
return mark(CE->getSubExpr());
if (ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(S))
return mark(EWC->getSubExpr());
if (Expr *E = dyn_cast<Expr>(S))
Removables.insert(E);
}
};
} // end anonymous namespace.
static bool HasSideEffects(Expr *E, ASTContext &Ctx) {
if (!E || !E->HasSideEffects(Ctx))
return false;
E = E->IgnoreParenCasts();
ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E);
if (!ME)
return true;
switch (ME->getMethodFamily()) {
case OMF_autorelease:
case OMF_dealloc:
case OMF_release:
case OMF_retain:
switch (ME->getReceiverKind()) {
case ObjCMessageExpr::SuperInstance:
return false;
case ObjCMessageExpr::Instance:
return HasSideEffects(ME->getInstanceReceiver(), Ctx);
default:
break;
}
break;
default:
break;
}
return true;
}
static void removeDeallocMethod(MigrationPass &pass) {
ASTContext &Ctx = pass.Ctx;
TransformActions &TA = pass.TA;
DeclContext *DC = Ctx.getTranslationUnitDecl();
ObjCMethodDecl *DeallocMethodDecl = 0;
IdentifierInfo *II = &Ctx.Idents.get("dealloc");
for (DeclContext::decl_iterator I = DC->decls_begin(), E = DC->decls_end();
I != E; ++I) {
Decl *D = *I;
if (ObjCImplementationDecl *IMD =
dyn_cast<ObjCImplementationDecl>(D)) {
DeallocMethodDecl = 0;
for (ObjCImplementationDecl::instmeth_iterator I =
IMD->instmeth_begin(), E = IMD->instmeth_end();
I != E; ++I) {
ObjCMethodDecl *OMD = *I;
if (OMD->isInstanceMethod() &&
OMD->getSelector() == Ctx.Selectors.getSelector(0, &II)) {
DeallocMethodDecl = OMD;
break;
}
}
if (DeallocMethodDecl &&
DeallocMethodDecl->getCompoundBody()->body_empty()) {
Transaction Trans(TA);
TA.remove(DeallocMethodDecl->getSourceRange());
}
}
}
}
namespace {
class ReferenceClear : public RecursiveASTVisitor<ReferenceClear> {
llvm::DenseSet<Expr *> &Refs;
public:
ReferenceClear(llvm::DenseSet<Expr *> &refs) : Refs(refs) { }
bool VisitDeclRefExpr(DeclRefExpr *E) { Refs.erase(E); return true; }
bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { Refs.erase(E); return true; }
void clearRefsIn(Stmt *S) { TraverseStmt(S); }
template <typename iterator>
void clearRefsIn(iterator begin, iterator end) {
for (; begin != end; ++begin)
TraverseStmt(*begin);
}
};
class ReferenceCollector : public RecursiveASTVisitor<ReferenceCollector> {
ValueDecl *Dcl;
llvm::DenseSet<Expr *> &Refs;
public:
ReferenceCollector(llvm::DenseSet<Expr *> &refs)
: Dcl(0), Refs(refs) { }
void lookFor(ValueDecl *D, Stmt *S) {
Dcl = D;
TraverseStmt(S);
}
bool VisitDeclRefExpr(DeclRefExpr *E) {
if (E->getDecl() == Dcl)
Refs.insert(E);
return true;
}
bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) {
if (E->getDecl() == Dcl)
Refs.insert(E);
return true;
}
};
class ReleaseCollector : public RecursiveASTVisitor<ReleaseCollector> {
Decl *Dcl;
llvm::SmallVectorImpl<ObjCMessageExpr *> &Releases;
public:
ReleaseCollector(Decl *D, llvm::SmallVectorImpl<ObjCMessageExpr *> &releases)
: Dcl(D), Releases(releases) { }
bool VisitObjCMessageExpr(ObjCMessageExpr *E) {
if (!E->isInstanceMessage())
return true;
if (E->getMethodFamily() != OMF_release)
return true;
Expr *instance = E->getInstanceReceiver()->IgnoreParenCasts();
if (DeclRefExpr *DE = dyn_cast<DeclRefExpr>(instance)) {
if (DE->getDecl() == Dcl)
Releases.push_back(E);
}
return true;
}
};
template <typename BODY_TRANS>
class BodyTransform : public RecursiveASTVisitor<BodyTransform<BODY_TRANS> > {
MigrationPass &Pass;
public:
BodyTransform(MigrationPass &pass) : Pass(pass) { }
void handleBody(Decl *D) {
Stmt *body = D->getBody();
if (body) {
BODY_TRANS(D, Pass).transformBody(body);
}
}
bool TraverseBlockDecl(BlockDecl *D) {
handleBody(D);
return true;
}
bool TraverseObjCMethodDecl(ObjCMethodDecl *D) {
if (D->isThisDeclarationADefinition())
handleBody(D);
return true;
}
bool TraverseFunctionDecl(FunctionDecl *D) {
if (D->isThisDeclarationADefinition())
handleBody(D);
return true;
}
};
} // anonymous namespace
//===----------------------------------------------------------------------===//
// makeAssignARCSafe
//===----------------------------------------------------------------------===//
namespace {
class ARCAssignChecker : public RecursiveASTVisitor<ARCAssignChecker> {
MigrationPass &Pass;
llvm::DenseSet<VarDecl *> ModifiedVars;
public:
ARCAssignChecker(MigrationPass &pass) : Pass(pass) { }
bool VisitBinaryOperator(BinaryOperator *Exp) {
Expr *E = Exp->getLHS();
SourceLocation OrigLoc = E->getExprLoc();
SourceLocation Loc = OrigLoc;
DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts());
if (declRef && isa<VarDecl>(declRef->getDecl())) {
ASTContext &Ctx = Pass.Ctx;
Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(Ctx, &Loc);
if (IsLV != Expr::MLV_ConstQualified)
return true;
VarDecl *var = cast<VarDecl>(declRef->getDecl());
if (var->isARCPseudoStrong()) {
Transaction Trans(Pass.TA);
if (Pass.TA.clearDiagnostic(diag::err_typecheck_arr_assign_enumeration,
Exp->getOperatorLoc())) {
if (!ModifiedVars.count(var)) {
TypeLoc TLoc = var->getTypeSourceInfo()->getTypeLoc();
Pass.TA.insert(TLoc.getBeginLoc(), "__strong ");
ModifiedVars.insert(var);
}
}
}
}
return true;
}
};
} // anonymous namespace
static void makeAssignARCSafe(MigrationPass &pass) {
ARCAssignChecker assignCheck(pass);
assignCheck.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// castNonObjCToObjC
//===----------------------------------------------------------------------===//
namespace {
class NonObjCToObjCCaster : public RecursiveASTVisitor<NonObjCToObjCCaster> {
MigrationPass &Pass;
public:
NonObjCToObjCCaster(MigrationPass &pass) : Pass(pass) { }
bool VisitCastExpr(CastExpr *E) {
if (E->getCastKind() != CK_AnyPointerToObjCPointerCast
&& E->getCastKind() != CK_BitCast)
return true;
QualType castType = E->getType();
Expr *castExpr = E->getSubExpr();
QualType castExprType = castExpr->getType();
if (castType->isObjCObjectPointerType() &&
castExprType->isObjCObjectPointerType())
return true;
if (!castType->isObjCObjectPointerType() &&
!castExprType->isObjCObjectPointerType())
return true;
bool exprRetainable = castExprType->isObjCIndirectLifetimeType();
bool castRetainable = castType->isObjCIndirectLifetimeType();
if (exprRetainable == castRetainable) return true;
if (castExpr->isNullPointerConstant(Pass.Ctx,
Expr::NPC_ValueDependentIsNull))
return true;
SourceLocation loc = castExpr->getExprLoc();
if (loc.isValid() && Pass.Ctx.getSourceManager().isInSystemHeader(loc))
return true;
if (castType->isObjCObjectPointerType())
transformNonObjCToObjCCast(E);
else
transformObjCToNonObjCCast(E);
return true;
}
private:
void transformNonObjCToObjCCast(CastExpr *E) {
if (!E) return;
// Global vars are assumed that are cast as unretained.
if (isGlobalVar(E))
if (E->getSubExpr()->getType()->isPointerType()) {
castToObjCObject(E, /*retained=*/false);
return;
}
// If the cast is directly over the result of a Core Foundation function
// try to figure out whether it should be cast as retained or unretained.
Expr *inner = E->IgnoreParenCasts();
if (CallExpr *callE = dyn_cast<CallExpr>(inner)) {
if (FunctionDecl *FD = callE->getDirectCallee()) {
if (FD->getAttr<CFReturnsRetainedAttr>()) {
castToObjCObject(E, /*retained=*/true);
return;
}
if (FD->getAttr<CFReturnsNotRetainedAttr>()) {
castToObjCObject(E, /*retained=*/false);
return;
}
if (FD->isGlobal() &&
FD->getIdentifier() &&
ento::cocoa::isRefType(E->getSubExpr()->getType(), "CF",
FD->getIdentifier()->getName())) {
StringRef fname = FD->getIdentifier()->getName();
if (fname.endswith("Retain") ||
fname.find("Create") != StringRef::npos ||
fname.find("Copy") != StringRef::npos) {
castToObjCObject(E, /*retained=*/true);
return;
}
if (fname.find("Get") != StringRef::npos) {
castToObjCObject(E, /*retained=*/false);
return;
}
}
}
}
}
void castToObjCObject(CastExpr *E, bool retained) {
TransformActions &TA = Pass.TA;
// We will remove the compiler diagnostic.
if (!TA.hasDiagnostic(diag::err_arc_mismatched_cast,
diag::err_arc_cast_requires_bridge,
E->getLocStart()))
return;
Transaction Trans(TA);
TA.clearDiagnostic(diag::err_arc_mismatched_cast,
diag::err_arc_cast_requires_bridge,
E->getLocStart());
if (CStyleCastExpr *CCE = dyn_cast<CStyleCastExpr>(E)) {
TA.insertAfterToken(CCE->getLParenLoc(), retained ? "__bridge_transfer "
: "__bridge ");
} else {
SourceLocation insertLoc = E->getSubExpr()->getLocStart();
llvm::SmallString<128> newCast;
newCast += '(';
newCast += retained ? "__bridge_transfer " : "__bridge ";
newCast += E->getType().getAsString(Pass.Ctx.PrintingPolicy);
newCast += ')';
if (isa<ParenExpr>(E->getSubExpr())) {
TA.insert(insertLoc, newCast.str());
} else {
newCast += '(';
TA.insert(insertLoc, newCast.str());
TA.insertAfterToken(E->getLocEnd(), ")");
}
}
}
void transformObjCToNonObjCCast(CastExpr *E) {
// FIXME: Handle these casts.
return;
#if 0
TransformActions &TA = Pass.TA;
// We will remove the compiler diagnostic.
if (!TA.hasDiagnostic(diag::err_arc_mismatched_cast,
diag::err_arc_cast_requires_bridge,
E->getLocStart()))
return;
Transaction Trans(TA);
TA.clearDiagnostic(diag::err_arc_mismatched_cast,
diag::err_arc_cast_requires_bridge,
E->getLocStart());
assert(!E->getType()->isObjCObjectPointerType());
bool shouldCast = !isa<CStyleCastExpr>(E) &&
!E->getType()->getPointeeType().isConstQualified();
SourceLocation loc = E->getSubExpr()->getLocStart();
if (isa<ParenExpr>(E->getSubExpr())) {
TA.insert(loc, shouldCast ? "(void*)objc_unretainedPointer"
: "objc_unretainedPointer");
} else {
TA.insert(loc, shouldCast ? "(void*)objc_unretainedPointer("
: "objc_unretainedPointer(");
TA.insertAfterToken(E->getLocEnd(), ")");
}
#endif
}
static bool isGlobalVar(Expr *E) {
E = E->IgnoreParenCasts();
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
return DRE->getDecl()->getDeclContext()->isFileContext();
if (ConditionalOperator *condOp = dyn_cast<ConditionalOperator>(E))
return isGlobalVar(condOp->getTrueExpr()) &&
isGlobalVar(condOp->getFalseExpr());
return false;
}
};
} // end anonymous namespace
static void castNonObjCToObjC(MigrationPass &pass) {
NonObjCToObjCCaster trans(pass);
trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// rewriteAllocCopyWithZone
//===----------------------------------------------------------------------===//
namespace {
class AllocCopyWithZoneRewriter :
public RecursiveASTVisitor<AllocCopyWithZoneRewriter> {
Decl *Dcl;
Stmt *Body;
MigrationPass &Pass;
Selector allocWithZoneSel;
Selector copyWithZoneSel;
Selector mutableCopyWithZoneSel;
Selector zoneSel;
IdentifierInfo *NSZoneII;
std::vector<DeclStmt *> NSZoneVars;
std::vector<Expr *> Removals;
public:
AllocCopyWithZoneRewriter(Decl *D, MigrationPass &pass)
: Dcl(D), Body(0), Pass(pass) {
SelectorTable &sels = pass.Ctx.Selectors;
IdentifierTable &ids = pass.Ctx.Idents;
allocWithZoneSel = sels.getUnarySelector(&ids.get("allocWithZone"));
copyWithZoneSel = sels.getUnarySelector(&ids.get("copyWithZone"));
mutableCopyWithZoneSel = sels.getUnarySelector(
&ids.get("mutableCopyWithZone"));
zoneSel = sels.getNullarySelector(&ids.get("zone"));
NSZoneII = &ids.get("_NSZone");
}
void transformBody(Stmt *body) {
Body = body;
// Don't change allocWithZone/copyWithZone messages inside
// custom implementations of such methods, it can lead to infinite loops.
if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(Dcl)) {
Selector sel = MD->getSelector();
if (sel == allocWithZoneSel ||
sel == copyWithZoneSel ||
sel == mutableCopyWithZoneSel ||
sel == zoneSel)
return;
}
TraverseStmt(body);
}
~AllocCopyWithZoneRewriter() {
for (std::vector<DeclStmt *>::reverse_iterator
I = NSZoneVars.rbegin(), E = NSZoneVars.rend(); I != E; ++I) {
DeclStmt *DS = *I;
DeclGroupRef group = DS->getDeclGroup();
std::vector<Expr *> varRemovals = Removals;
bool areAllVarsUnused = true;
for (std::reverse_iterator<DeclGroupRef::iterator>
DI(group.end()), DE(group.begin()); DI != DE; ++DI) {
VarDecl *VD = cast<VarDecl>(*DI);
if (isNSZoneVarUsed(VD, varRemovals)) {
areAllVarsUnused = false;
break;
}
varRemovals.push_back(VD->getInit());
}
if (areAllVarsUnused) {
Transaction Trans(Pass.TA);
clearUnavailableDiags(DS);
Pass.TA.removeStmt(DS);
Removals.swap(varRemovals);
}
}
}
bool VisitObjCMessageExpr(ObjCMessageExpr *E) {
if (!isAllocCopyWithZoneCall(E))
return true;
Expr *arg = E->getArg(0);
if (paramToAllocWithZoneHasSideEffects(arg))
return true;
Pass.TA.startTransaction();
clearUnavailableDiags(arg);
Pass.TA.clearDiagnostic(diag::err_unavailable_message,
E->getReceiverRange().getBegin());
Pass.TA.remove(SourceRange(E->getSelectorLoc(), arg->getLocEnd()));
StringRef rewrite;
if (E->getSelector() == allocWithZoneSel)
rewrite = "alloc";
else if (E->getSelector() == copyWithZoneSel)
rewrite = "copy";
else {
assert(E->getSelector() == mutableCopyWithZoneSel);
rewrite = "mutableCopy";
}
Pass.TA.insert(E->getSelectorLoc(), rewrite);
bool failed = Pass.TA.commitTransaction();
if (!failed)
Removals.push_back(arg);
return true;
}
bool VisitDeclStmt(DeclStmt *DS) {
DeclGroupRef group = DS->getDeclGroup();
if (group.begin() == group.end())
return true;
for (DeclGroupRef::iterator
DI = group.begin(), DE = group.end(); DI != DE; ++DI)
if (!isRemovableNSZoneVar(*DI))
return true;
NSZoneVars.push_back(DS);
return true;
}
private:
bool isRemovableNSZoneVar(Decl *D) {
if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
if (isNSZone(VD->getType()))
return !paramToAllocWithZoneHasSideEffects(VD->getInit());
}
return false;
}
bool isNSZone(RecordDecl *RD) {
return RD && RD->getIdentifier() == NSZoneII;
}
bool isNSZone(QualType Ty) {
QualType pointee = Ty->getPointeeType();
if (pointee.isNull())
return false;
if (const RecordType *recT = pointee->getAsStructureType())
return isNSZone(recT->getDecl());
return false;
}
bool isNSZoneVarUsed(VarDecl *D, std::vector<Expr *> &removals) {
llvm::DenseSet<Expr *> refs;
ReferenceCollector refColl(refs);
refColl.lookFor(D, Body);
ReferenceClear refClear(refs);
refClear.clearRefsIn(removals.begin(), removals.end());
return !refs.empty();
}
bool isAllocCopyWithZoneCall(ObjCMessageExpr *E) {
if (E->getNumArgs() == 1 &&
E->getSelector() == allocWithZoneSel &&
(E->isClassMessage() ||
Pass.TA.hasDiagnostic(diag::err_unavailable_message,
E->getReceiverRange().getBegin())))
return true;
return E->isInstanceMessage() &&
E->getNumArgs() == 1 &&
(E->getSelector() == copyWithZoneSel ||
E->getSelector() == mutableCopyWithZoneSel);
}
bool isZoneCall(ObjCMessageExpr *E) {
return E->isInstanceMessage() &&
E->getNumArgs() == 0 &&
E->getSelector() == zoneSel;
}
bool paramToAllocWithZoneHasSideEffects(Expr *E) {
if (!HasSideEffects(E, Pass.Ctx))
return false;
E = E->IgnoreParenCasts();
ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E);
if (!ME)
return true;
if (!isZoneCall(ME))
return true;
return HasSideEffects(ME->getInstanceReceiver(), Pass.Ctx);
}
void clearUnavailableDiags(Stmt *S) {
if (S)
Pass.TA.clearDiagnostic(diag::err_unavailable,
diag::err_unavailable_message,
S->getSourceRange());
}
};
} // end anonymous namespace
static void rewriteAllocCopyWithZone(MigrationPass &pass) {
BodyTransform<AllocCopyWithZoneRewriter> trans(pass);
trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// rewriteAutoreleasePool
//===----------------------------------------------------------------------===//
/// \brief 'Loc' is the end of a statement range. This returns the location
/// immediately after the semicolon following the statement.
/// If no semicolon is found or the location is inside a macro, the returned
/// source location will be invalid.
static SourceLocation findLocationAfterSemi(ASTContext &Ctx,
SourceLocation loc) {
SourceManager &SM = Ctx.getSourceManager();
if (loc.isMacroID()) {
if (!SM.isAtEndOfMacroInstantiation(loc))
return SourceLocation();
loc = SM.getInstantiationRange(loc).second;
}
loc = Lexer::getLocForEndOfToken(loc, /*Offset=*/0, SM, Ctx.getLangOptions());
// Break down the source location.
std::pair<FileID, unsigned> locInfo = SM.getDecomposedLoc(loc);
// Try to load the file buffer.
bool invalidTemp = false;
llvm::StringRef file = SM.getBufferData(locInfo.first, &invalidTemp);
if (invalidTemp)
return SourceLocation();
const char *tokenBegin = file.data() + locInfo.second;
// Lex from the start of the given location.
Lexer lexer(SM.getLocForStartOfFile(locInfo.first),
Ctx.getLangOptions(),
file.begin(), tokenBegin, file.end());
Token tok;
lexer.LexFromRawLexer(tok);
if (tok.isNot(tok::semi))
return SourceLocation();
return tok.getLocation().getFileLocWithOffset(1);
}
namespace {
class AutoreleasePoolRewriter
: public RecursiveASTVisitor<AutoreleasePoolRewriter> {
public:
AutoreleasePoolRewriter(Decl *D, MigrationPass &pass)
: Dcl(D), Body(0), Pass(pass) {
PoolII = &pass.Ctx.Idents.get("NSAutoreleasePool");
DrainSel = pass.Ctx.Selectors.getNullarySelector(
&pass.Ctx.Idents.get("drain"));
}
void transformBody(Stmt *body) {
Body = body;
TraverseStmt(body);
}
~AutoreleasePoolRewriter() {
llvm::SmallVector<VarDecl *, 8> VarsToHandle;
for (std::map<VarDecl *, PoolVarInfo>::iterator
I = PoolVars.begin(), E = PoolVars.end(); I != E; ++I) {
VarDecl *var = I->first;
PoolVarInfo &info = I->second;
// Check that we can handle/rewrite all references of the pool.
ReferenceClear refClear(info.Refs);
refClear.clearRefsIn(info.Dcl);
for (llvm::SmallVectorImpl<PoolScope>::iterator
scpI = info.Scopes.begin(),
scpE = info.Scopes.end(); scpI != scpE; ++scpI) {
PoolScope &scope = *scpI;
refClear.clearRefsIn(*scope.Begin);
refClear.clearRefsIn(*scope.End);
refClear.clearRefsIn(scope.Releases.begin(), scope.Releases.end());
}
// Even if one reference is not handled we will not do anything about that
// pool variable.
if (info.Refs.empty())
VarsToHandle.push_back(var);
}
for (unsigned i = 0, e = VarsToHandle.size(); i != e; ++i) {
PoolVarInfo &info = PoolVars[VarsToHandle[i]];
Transaction Trans(Pass.TA);
clearUnavailableDiags(info.Dcl);
Pass.TA.removeStmt(info.Dcl);
// Add "@autoreleasepool { }"
for (llvm::SmallVectorImpl<PoolScope>::iterator
scpI = info.Scopes.begin(),
scpE = info.Scopes.end(); scpI != scpE; ++scpI) {
PoolScope &scope = *scpI;
clearUnavailableDiags(*scope.Begin);
clearUnavailableDiags(*scope.End);
if (scope.IsFollowedBySimpleReturnStmt) {
// Include the return in the scope.
Pass.TA.replaceStmt(*scope.Begin, "@autoreleasepool {");
Pass.TA.removeStmt(*scope.End);
Stmt::child_iterator retI = scope.End;
++retI;
SourceLocation afterSemi = findLocationAfterSemi(Pass.Ctx,
(*retI)->getLocEnd());
assert(afterSemi.isValid() &&
"Didn't we check before setting IsFollowedBySimpleReturnStmt "
"to true?");
Pass.TA.insertAfterToken(afterSemi, "\n}");
Pass.TA.increaseIndentation(
SourceRange(scope.getIndentedRange().getBegin(),
(*retI)->getLocEnd()),
scope.CompoundParent->getLocStart());
} else {
Pass.TA.replaceStmt(*scope.Begin, "@autoreleasepool {");
Pass.TA.replaceStmt(*scope.End, "}");
Pass.TA.increaseIndentation(scope.getIndentedRange(),
scope.CompoundParent->getLocStart());
}
}
// Remove rest of pool var references.
for (llvm::SmallVectorImpl<PoolScope>::iterator
scpI = info.Scopes.begin(),
scpE = info.Scopes.end(); scpI != scpE; ++scpI) {
PoolScope &scope = *scpI;
for (llvm::SmallVectorImpl<ObjCMessageExpr *>::iterator
relI = scope.Releases.begin(),
relE = scope.Releases.end(); relI != relE; ++relI) {
clearUnavailableDiags(*relI);
Pass.TA.removeStmt(*relI);
}
}
}
}
bool VisitCompoundStmt(CompoundStmt *S) {
llvm::SmallVector<PoolScope, 4> Scopes;
for (Stmt::child_iterator
I = S->body_begin(), E = S->body_end(); I != E; ++I) {
Stmt *child = getEssential(*I);
if (DeclStmt *DclS = dyn_cast<DeclStmt>(child)) {
if (DclS->isSingleDecl()) {
if (VarDecl *VD = dyn_cast<VarDecl>(DclS->getSingleDecl())) {
if (isNSAutoreleasePool(VD->getType())) {
PoolVarInfo &info = PoolVars[VD];
info.Dcl = DclS;
ReferenceCollector refColl(info.Refs);
refColl.lookFor(VD, S);
// Does this statement follow the pattern:
// NSAutoreleasePool * pool = [NSAutoreleasePool new];
if (isPoolCreation(VD->getInit())) {
Scopes.push_back(PoolScope());
Scopes.back().PoolVar = VD;
Scopes.back().CompoundParent = S;
Scopes.back().Begin = I;
}
}
}
}
} else if (BinaryOperator *bop = dyn_cast<BinaryOperator>(child)) {
if (DeclRefExpr *dref = dyn_cast<DeclRefExpr>(bop->getLHS())) {
if (VarDecl *VD = dyn_cast<VarDecl>(dref->getDecl())) {
// Does this statement follow the pattern:
// pool = [NSAutoreleasePool new];
if (isNSAutoreleasePool(VD->getType()) &&
isPoolCreation(bop->getRHS())) {
Scopes.push_back(PoolScope());
Scopes.back().PoolVar = VD;
Scopes.back().CompoundParent = S;
Scopes.back().Begin = I;
}
}
}
}
if (Scopes.empty())
continue;
if (isPoolDrain(Scopes.back().PoolVar, child)) {
PoolScope &scope = Scopes.back();
scope.End = I;
handlePoolScope(scope, S);
Scopes.pop_back();
}
}
return true;
}
private:
void clearUnavailableDiags(Stmt *S) {
if (S)
Pass.TA.clearDiagnostic(diag::err_unavailable,
diag::err_unavailable_message,
S->getSourceRange());
}
struct PoolScope {
VarDecl *PoolVar;
CompoundStmt *CompoundParent;
Stmt::child_iterator Begin;
Stmt::child_iterator End;
bool IsFollowedBySimpleReturnStmt;
llvm::SmallVector<ObjCMessageExpr *, 4> Releases;
PoolScope() : PoolVar(0), CompoundParent(0), Begin(), End(),
IsFollowedBySimpleReturnStmt(false) { }
SourceRange getIndentedRange() const {
Stmt::child_iterator rangeS = Begin;
++rangeS;
if (rangeS == End)
return SourceRange();
Stmt::child_iterator rangeE = Begin;
for (Stmt::child_iterator I = rangeS; I != End; ++I)
++rangeE;
return SourceRange((*rangeS)->getLocStart(), (*rangeE)->getLocEnd());
}
};
class NameReferenceChecker : public RecursiveASTVisitor<NameReferenceChecker>{
ASTContext &Ctx;
SourceRange ScopeRange;
SourceLocation &referenceLoc, &declarationLoc;
public:
NameReferenceChecker(ASTContext &ctx, PoolScope &scope,
SourceLocation &referenceLoc,
SourceLocation &declarationLoc)
: Ctx(ctx), referenceLoc(referenceLoc),
declarationLoc(declarationLoc) {
ScopeRange = SourceRange((*scope.Begin)->getLocStart(),
(*scope.End)->getLocStart());
}
bool VisitDeclRefExpr(DeclRefExpr *E) {
return checkRef(E->getLocation(), E->getDecl()->getLocation());
}
bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) {
return checkRef(E->getLocation(), E->getDecl()->getLocation());
}
bool VisitTypedefTypeLoc(TypedefTypeLoc TL) {
return checkRef(TL.getBeginLoc(), TL.getTypedefNameDecl()->getLocation());
}
bool VisitTagTypeLoc(TagTypeLoc TL) {
return checkRef(TL.getBeginLoc(), TL.getDecl()->getLocation());
}
private:
bool checkRef(SourceLocation refLoc, SourceLocation declLoc) {
if (isInScope(declLoc)) {
referenceLoc = refLoc;
declarationLoc = declLoc;
return false;
}
return true;
}
bool isInScope(SourceLocation loc) {
SourceManager &SM = Ctx.getSourceManager();
if (SM.isBeforeInTranslationUnit(loc, ScopeRange.getBegin()))
return false;
return SM.isBeforeInTranslationUnit(loc, ScopeRange.getEnd());
}
};
void handlePoolScope(PoolScope &scope, CompoundStmt *compoundS) {
// Check that all names declared inside the scope are not used
// outside the scope.
{
bool nameUsedOutsideScope = false;
SourceLocation referenceLoc, declarationLoc;
Stmt::child_iterator SI = scope.End, SE = compoundS->body_end();
++SI;
// Check if the autoreleasepool scope is followed by a simple return
// statement, in which case we will include the return in the scope.
if (SI != SE)
if (ReturnStmt *retS = dyn_cast<ReturnStmt>(*SI))
if ((retS->getRetValue() == 0 ||
isa<DeclRefExpr>(retS->getRetValue()->IgnoreParenCasts())) &&
findLocationAfterSemi(Pass.Ctx, retS->getLocEnd()).isValid()) {
scope.IsFollowedBySimpleReturnStmt = true;
++SI; // the return will be included in scope, don't check it.
}
for (; SI != SE; ++SI) {
nameUsedOutsideScope = !NameReferenceChecker(Pass.Ctx, scope,
referenceLoc,
declarationLoc).TraverseStmt(*SI);
if (nameUsedOutsideScope)
break;
}
// If not all references were cleared it means some variables/typenames/etc
// declared inside the pool scope are used outside of it.
// We won't try to rewrite the pool.
if (nameUsedOutsideScope) {
Pass.TA.reportError("a name is referenced outside the "
"NSAutoreleasePool scope that it was declared in", referenceLoc);
Pass.TA.reportNote("name declared here", declarationLoc);
Pass.TA.reportNote("intended @autoreleasepool scope begins here",
(*scope.Begin)->getLocStart());
Pass.TA.reportNote("intended @autoreleasepool scope ends here",
(*scope.End)->getLocStart());
return;
}
}
// Collect all releases of the pool; they will be removed.
{
ReleaseCollector releaseColl(scope.PoolVar, scope.Releases);
Stmt::child_iterator I = scope.Begin;
++I;
for (; I != scope.End; ++I)
releaseColl.TraverseStmt(*I);
}
PoolVars[scope.PoolVar].Scopes.push_back(scope);
}
bool isPoolCreation(Expr *E) {
if (!E) return false;
E = getEssential(E);
ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E);
if (!ME) return false;
if (ME->getMethodFamily() == OMF_new &&
ME->getReceiverKind() == ObjCMessageExpr::Class &&
isNSAutoreleasePool(ME->getReceiverInterface()))
return true;
if (ME->getReceiverKind() == ObjCMessageExpr::Instance &&
ME->getMethodFamily() == OMF_init) {
Expr *rec = getEssential(ME->getInstanceReceiver());
if (ObjCMessageExpr *recME = dyn_cast_or_null<ObjCMessageExpr>(rec)) {
if (recME->getMethodFamily() == OMF_alloc &&
recME->getReceiverKind() == ObjCMessageExpr::Class &&
isNSAutoreleasePool(recME->getReceiverInterface()))
return true;
}
}
return false;
}
bool isPoolDrain(VarDecl *poolVar, Stmt *S) {
if (!S) return false;
S = getEssential(S);
ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S);
if (!ME) return false;
if (ME->getReceiverKind() == ObjCMessageExpr::Instance) {
Expr *rec = getEssential(ME->getInstanceReceiver());
if (DeclRefExpr *dref = dyn_cast<DeclRefExpr>(rec))
if (dref->getDecl() == poolVar)
return ME->getMethodFamily() == OMF_release ||
ME->getSelector() == DrainSel;
}
return false;
}
bool isNSAutoreleasePool(ObjCInterfaceDecl *IDecl) {
return IDecl && IDecl->getIdentifier() == PoolII;
}
bool isNSAutoreleasePool(QualType Ty) {
QualType pointee = Ty->getPointeeType();
if (pointee.isNull())
return false;
if (const ObjCInterfaceType *interT = pointee->getAs<ObjCInterfaceType>())
return isNSAutoreleasePool(interT->getDecl());
return false;
}
static Expr *getEssential(Expr *E) {
return cast<Expr>(getEssential((Stmt*)E));
}
static Stmt *getEssential(Stmt *S) {
if (ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(S))
S = EWC->getSubExpr();
if (Expr *E = dyn_cast<Expr>(S))
S = E->IgnoreParenCasts();
return S;
}
Decl *Dcl;
Stmt *Body;
MigrationPass &Pass;
IdentifierInfo *PoolII;
Selector DrainSel;
struct PoolVarInfo {
DeclStmt *Dcl;
llvm::DenseSet<Expr *> Refs;
llvm::SmallVector<PoolScope, 2> Scopes;
PoolVarInfo() : Dcl(0) { }
};
std::map<VarDecl *, PoolVarInfo> PoolVars;
};
} // anonymous namespace
static void rewriteAutoreleasePool(MigrationPass &pass) {
BodyTransform<AutoreleasePoolRewriter> trans(pass);
trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// removeRetainReleaseDealloc
//===----------------------------------------------------------------------===//
namespace {
class RetainReleaseDeallocRemover :
public RecursiveASTVisitor<RetainReleaseDeallocRemover> {
Decl *Dcl;
Stmt *Body;
MigrationPass &Pass;
llvm::DenseSet<Expr *> Removables;
llvm::OwningPtr<ParentMap> StmtMap;
public:
RetainReleaseDeallocRemover(Decl *D, MigrationPass &pass)
: Dcl(D), Body(0), Pass(pass) { }
void transformBody(Stmt *body) {
Body = body;
RemovablesCollector(Removables).TraverseStmt(body);
StmtMap.reset(new ParentMap(body));
TraverseStmt(body);
}
bool VisitObjCMessageExpr(ObjCMessageExpr *E) {
switch (E->getMethodFamily()) {
default:
return true;
case OMF_retain:
case OMF_release:
case OMF_autorelease:
if (E->getReceiverKind() == ObjCMessageExpr::Instance)
if (Expr *rec = E->getInstanceReceiver()) {
rec = rec->IgnoreParenImpCasts();
if (rec->getType().getObjCLifetime() == Qualifiers::OCL_ExplicitNone){
std::string err = "It is not safe to remove '";
err += E->getSelector().getAsString() + "' message on "
"an __unsafe_unretained type";
Pass.TA.reportError(err, rec->getLocStart());
return true;
}
}
case OMF_dealloc:
break;
}
switch (E->getReceiverKind()) {
default:
return true;
case ObjCMessageExpr::SuperInstance: {
Transaction Trans(Pass.TA);
Pass.TA.clearDiagnostic(diag::err_arc_illegal_explicit_message,
diag::err_unavailable,
diag::err_unavailable_message,
E->getSuperLoc());
if (tryRemoving(E))
return true;
Pass.TA.replace(E->getSourceRange(), "self");
return true;
}
case ObjCMessageExpr::Instance:
break;
}
Expr *rec = E->getInstanceReceiver();
if (!rec) return true;
Transaction Trans(Pass.TA);
Pass.TA.clearDiagnostic(diag::err_arc_illegal_explicit_message,
diag::err_unavailable,
diag::err_unavailable_message,
rec->getExprLoc());
if (!HasSideEffects(E, Pass.Ctx)) {
if (tryRemoving(E))
return true;
}
Pass.TA.replace(E->getSourceRange(), rec->getSourceRange());
return true;
}
private:
bool isRemovable(Expr *E) const {
return Removables.count(E);
}
bool tryRemoving(Expr *E) const {
if (isRemovable(E)) {
Pass.TA.removeStmt(E);
return true;
}
if (ParenExpr *parenE = dyn_cast_or_null<ParenExpr>(StmtMap->getParent(E)))
return tryRemoving(parenE);
if (BinaryOperator *
bopE = dyn_cast_or_null<BinaryOperator>(StmtMap->getParent(E))) {
if (bopE->getOpcode() == BO_Comma && bopE->getLHS() == E &&
isRemovable(bopE)) {
Pass.TA.replace(bopE->getSourceRange(), bopE->getRHS()->getSourceRange());
return true;
}
}
return false;
}
};
} // anonymous namespace
static void removeRetainReleaseDealloc(MigrationPass &pass) {
BodyTransform<RetainReleaseDeallocRemover> trans(pass);
trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// removeEmptyStatements
//===----------------------------------------------------------------------===//
namespace {
class EmptyStatementsRemover :
public RecursiveASTVisitor<EmptyStatementsRemover> {
MigrationPass &Pass;
llvm::DenseSet<unsigned> MacroLocs;
public:
EmptyStatementsRemover(MigrationPass &pass) : Pass(pass) {
for (unsigned i = 0, e = Pass.ARCMTMacroLocs.size(); i != e; ++i)
MacroLocs.insert(Pass.ARCMTMacroLocs[i].getRawEncoding());
}
bool TraverseStmtExpr(StmtExpr *E) {
CompoundStmt *S = E->getSubStmt();
for (CompoundStmt::body_iterator
I = S->body_begin(), E = S->body_end(); I != E; ++I) {
if (I != E - 1)
check(*I);
TraverseStmt(*I);
}
return true;
}
bool VisitCompoundStmt(CompoundStmt *S) {
for (CompoundStmt::body_iterator
I = S->body_begin(), E = S->body_end(); I != E; ++I)
check(*I);
return true;
}
bool isMacroLoc(SourceLocation loc) {
if (loc.isInvalid()) return false;
return MacroLocs.count(loc.getRawEncoding());
}
ASTContext &getContext() { return Pass.Ctx; }
private:
/// \brief Returns true if the statement became empty due to previous
/// transformations.
class EmptyChecker : public StmtVisitor<EmptyChecker, bool> {
EmptyStatementsRemover &Trans;
public:
EmptyChecker(EmptyStatementsRemover &trans) : Trans(trans) { }
bool VisitNullStmt(NullStmt *S) {
return Trans.isMacroLoc(S->getLeadingEmptyMacroLoc());
}
bool VisitCompoundStmt(CompoundStmt *S) {
if (S->body_empty())
return false; // was already empty, not because of transformations.
for (CompoundStmt::body_iterator
I = S->body_begin(), E = S->body_end(); I != E; ++I)
if (!Visit(*I))
return false;
return true;
}
bool VisitIfStmt(IfStmt *S) {
if (S->getConditionVariable())
return false;
Expr *condE = S->getCond();
if (!condE)
return false;
if (HasSideEffects(condE, Trans.getContext()))
return false;
if (!S->getThen() || !Visit(S->getThen()))
return false;
if (S->getElse() && !Visit(S->getElse()))
return false;
return true;
}
bool VisitWhileStmt(WhileStmt *S) {
if (S->getConditionVariable())
return false;
Expr *condE = S->getCond();
if (!condE)
return false;
if (HasSideEffects(condE, Trans.getContext()))
return false;
if (!S->getBody())
return false;
return Visit(S->getBody());
}
bool VisitDoStmt(DoStmt *S) {
Expr *condE = S->getCond();
if (!condE)
return false;
if (HasSideEffects(condE, Trans.getContext()))
return false;
if (!S->getBody())
return false;
return Visit(S->getBody());
}
bool VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
Expr *Exp = S->getCollection();
if (!Exp)
return false;
if (HasSideEffects(Exp, Trans.getContext()))
return false;
if (!S->getBody())
return false;
return Visit(S->getBody());
}
bool VisitObjCAutoreleasePoolStmt(ObjCAutoreleasePoolStmt *S) {
if (!S->getSubStmt())
return false;
return Visit(S->getSubStmt());
}
};
void check(Stmt *S) {
if (!S) return;
if (EmptyChecker(*this).Visit(S)) {
Transaction Trans(Pass.TA);
Pass.TA.removeStmt(S);
}
}
};
} // anonymous namespace
static void removeEmptyStatements(MigrationPass &pass) {
EmptyStatementsRemover(pass).TraverseDecl(pass.Ctx.getTranslationUnitDecl());
for (unsigned i = 0, e = pass.ARCMTMacroLocs.size(); i != e; ++i) {
Transaction Trans(pass.TA);
pass.TA.remove(pass.ARCMTMacroLocs[i]);
}
}
//===----------------------------------------------------------------------===//
// changeIvarsOfAssignProperties.
//===----------------------------------------------------------------------===//
namespace {
class AssignPropertiesTrans {
MigrationPass &Pass;
struct PropData {
ObjCPropertyDecl *PropD;
ObjCIvarDecl *IvarD;
bool ShouldChangeToWeak;
SourceLocation ArcPropAssignErrorLoc;
};
typedef llvm::SmallVector<PropData, 2> PropsTy;
typedef llvm::DenseMap<unsigned, PropsTy> PropsMapTy;
PropsMapTy PropsMap;
public:
AssignPropertiesTrans(MigrationPass &pass) : Pass(pass) { }
void doTransform(ObjCImplementationDecl *D) {
SourceManager &SM = Pass.Ctx.getSourceManager();
ObjCInterfaceDecl *IFace = D->getClassInterface();
for (ObjCInterfaceDecl::prop_iterator
I = IFace->prop_begin(), E = IFace->prop_end(); I != E; ++I) {
ObjCPropertyDecl *propD = *I;
unsigned loc = SM.getInstantiationLoc(propD->getAtLoc()).getRawEncoding();
PropsTy &props = PropsMap[loc];
props.push_back(PropData());
props.back().PropD = propD;
props.back().IvarD = 0;
props.back().ShouldChangeToWeak = false;
}
typedef DeclContext::specific_decl_iterator<ObjCPropertyImplDecl>
prop_impl_iterator;
for (prop_impl_iterator
I = prop_impl_iterator(D->decls_begin()),
E = prop_impl_iterator(D->decls_end()); I != E; ++I) {
VisitObjCPropertyImplDecl(*I);
}
for (PropsMapTy::iterator
I = PropsMap.begin(), E = PropsMap.end(); I != E; ++I) {
SourceLocation atLoc = SourceLocation::getFromRawEncoding(I->first);
PropsTy &props = I->second;
if (shouldApplyWeakToAllProp(props)) {
if (changeAssignToWeak(atLoc)) {
// Couldn't add the 'weak' property attribute,
// try adding __unsafe_unretained.
applyUnsafeUnretained(props);
} else {
for (PropsTy::iterator
PI = props.begin(), PE = props.end(); PI != PE; ++PI) {
applyWeak(*PI);
}
}
} else {
// We should not add 'weak' attribute since not all properties need it.
// So just add __unsafe_unretained to the ivars.
applyUnsafeUnretained(props);
}
}
}
bool shouldApplyWeakToAllProp(PropsTy &props) {
for (PropsTy::iterator
PI = props.begin(), PE = props.end(); PI != PE; ++PI) {
if (!PI->ShouldChangeToWeak)
return false;
}
return true;
}
void applyWeak(PropData &prop) {
assert(!Pass.Ctx.getLangOptions().ObjCNoAutoRefCountRuntime);
Transaction Trans(Pass.TA);
Pass.TA.insert(prop.IvarD->getLocation(), "__weak ");
Pass.TA.clearDiagnostic(diag::err_arc_assign_property_lifetime,
prop.ArcPropAssignErrorLoc);
}
void applyUnsafeUnretained(PropsTy &props) {
for (PropsTy::iterator
PI = props.begin(), PE = props.end(); PI != PE; ++PI) {
if (PI->ShouldChangeToWeak) {
Transaction Trans(Pass.TA);
Pass.TA.insert(PI->IvarD->getLocation(), "__unsafe_unretained ");
Pass.TA.clearDiagnostic(diag::err_arc_assign_property_lifetime,
PI->ArcPropAssignErrorLoc);
}
}
}
bool VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
SourceManager &SM = Pass.Ctx.getSourceManager();
if (D->getPropertyImplementation() != ObjCPropertyImplDecl::Synthesize)
return true;
ObjCPropertyDecl *propD = D->getPropertyDecl();
if (!propD || propD->isInvalidDecl())
return true;
ObjCIvarDecl *ivarD = D->getPropertyIvarDecl();
if (!ivarD || ivarD->isInvalidDecl())
return true;
if (!(propD->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_assign))
return true;
if (isa<AttributedType>(ivarD->getType().getTypePtr()))
return true;
if (ivarD->getType().getLocalQualifiers().getObjCLifetime()
!= Qualifiers::OCL_Strong)
return true;
if (!Pass.TA.hasDiagnostic(
diag::err_arc_assign_property_lifetime, D->getLocation()))
return true;
// There is a "error: existing ivar for assign property must be
// __unsafe_unretained"; fix it.
if (Pass.Ctx.getLangOptions().ObjCNoAutoRefCountRuntime) {
// We will just add __unsafe_unretained to the ivar.
Transaction Trans(Pass.TA);
Pass.TA.insert(ivarD->getLocation(), "__unsafe_unretained ");
Pass.TA.clearDiagnostic(
diag::err_arc_assign_property_lifetime, D->getLocation());
} else {
// Mark that we want the ivar to become weak.
unsigned loc = SM.getInstantiationLoc(propD->getAtLoc()).getRawEncoding();
PropsTy &props = PropsMap[loc];
for (PropsTy::iterator I = props.begin(), E = props.end(); I != E; ++I) {
if (I->PropD == propD) {
I->IvarD = ivarD;
I->ShouldChangeToWeak = true;
I->ArcPropAssignErrorLoc = D->getLocation();
}
}
}
return true;
}
private:
bool changeAssignToWeak(SourceLocation atLoc) {
SourceManager &SM = Pass.Ctx.getSourceManager();
// Break down the source location.
std::pair<FileID, unsigned> locInfo = SM.getDecomposedLoc(atLoc);
// Try to load the file buffer.
bool invalidTemp = false;
llvm::StringRef file = SM.getBufferData(locInfo.first, &invalidTemp);
if (invalidTemp)
return true;
const char *tokenBegin = file.data() + locInfo.second;
// Lex from the start of the given location.
Lexer lexer(SM.getLocForStartOfFile(locInfo.first),
Pass.Ctx.getLangOptions(),
file.begin(), tokenBegin, file.end());
Token tok;
lexer.LexFromRawLexer(tok);
if (tok.isNot(tok::at)) return true;
lexer.LexFromRawLexer(tok);
if (tok.isNot(tok::raw_identifier)) return true;
if (llvm::StringRef(tok.getRawIdentifierData(), tok.getLength())
!= "property")
return true;
lexer.LexFromRawLexer(tok);
if (tok.isNot(tok::l_paren)) return true;
SourceLocation LParen = tok.getLocation();
SourceLocation assignLoc;
bool isEmpty = false;
lexer.LexFromRawLexer(tok);
if (tok.is(tok::r_paren)) {
isEmpty = true;
} else {
while (1) {
if (tok.isNot(tok::raw_identifier)) return true;
llvm::StringRef ident(tok.getRawIdentifierData(), tok.getLength());
if (ident == "assign")
assignLoc = tok.getLocation();
do {
lexer.LexFromRawLexer(tok);
} while (tok.isNot(tok::comma) && tok.isNot(tok::r_paren));
if (tok.is(tok::r_paren))
break;
lexer.LexFromRawLexer(tok);
}
}
Transaction Trans(Pass.TA);
if (assignLoc.isValid())
Pass.TA.replaceText(assignLoc, "assign", "weak");
else
Pass.TA.insertAfterToken(LParen, isEmpty ? "weak" : "weak, ");
return false;
}
};
class PropertiesChecker : public RecursiveASTVisitor<PropertiesChecker> {
MigrationPass &Pass;
public:
PropertiesChecker(MigrationPass &pass) : Pass(pass) { }
bool TraverseObjCImplementationDecl(ObjCImplementationDecl *D) {
AssignPropertiesTrans(Pass).doTransform(D);
return true;
}
};
} // anonymous namespace
static void changeIvarsOfAssignProperties(MigrationPass &pass) {
PropertiesChecker(pass).TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// rewriteUnusedDelegateInit
//===----------------------------------------------------------------------===//
namespace {
class UnusedInitRewriter : public RecursiveASTVisitor<UnusedInitRewriter> {
Decl *Dcl;
Stmt *Body;
MigrationPass &Pass;
llvm::DenseSet<Expr *> Removables;
public:
UnusedInitRewriter(Decl *D, MigrationPass &pass)
: Dcl(D), Body(0), Pass(pass) { }
void transformBody(Stmt *body) {
Body = body;
RemovablesCollector(Removables).TraverseStmt(body);
TraverseStmt(body);
}
bool VisitObjCMessageExpr(ObjCMessageExpr *ME) {
if (ME->isDelegateInitCall() &&
isRemovable(ME) &&
Pass.TA.hasDiagnostic(diag::err_arc_unused_init_message,
ME->getExprLoc())) {
Transaction Trans(Pass.TA);
Pass.TA.clearDiagnostic(diag::err_arc_unused_init_message,
ME->getExprLoc());
Pass.TA.insert(ME->getExprLoc(), "self = ");
}
return true;
}
private:
bool isRemovable(Expr *E) const {
return Removables.count(E);
}
};
} // anonymous namespace
static void rewriteUnusedDelegateInit(MigrationPass &pass) {
BodyTransform<UnusedInitRewriter> trans(pass);
trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// rewriteBlockObjCVariable
//===----------------------------------------------------------------------===//
namespace {
class RootBlockObjCVarRewriter :
public RecursiveASTVisitor<RootBlockObjCVarRewriter> {
MigrationPass &Pass;
llvm::DenseSet<VarDecl *> CheckedVars;
class BlockVarChecker : public RecursiveASTVisitor<BlockVarChecker> {
VarDecl *Var;
typedef RecursiveASTVisitor<BlockVarChecker> base;
public:
BlockVarChecker(VarDecl *var) : Var(var) { }
bool TraverseImplicitCastExpr(ImplicitCastExpr *castE) {
if (BlockDeclRefExpr *
ref = dyn_cast<BlockDeclRefExpr>(castE->getSubExpr())) {
if (ref->getDecl() == Var) {
if (castE->getCastKind() == CK_LValueToRValue)
return true; // Using the value of the variable.
if (castE->getCastKind() == CK_NoOp && castE->isLValue() &&
Var->getASTContext().getLangOptions().CPlusPlus)
return true; // Binding to const C++ reference.
}
}
return base::TraverseImplicitCastExpr(castE);
}
bool VisitBlockDeclRefExpr(BlockDeclRefExpr *E) {
if (E->getDecl() == Var)
return false; // The reference of the variable, and not just its value,
// is needed.
return true;
}
};
public:
RootBlockObjCVarRewriter(MigrationPass &pass) : Pass(pass) { }
bool VisitBlockDecl(BlockDecl *block) {
llvm::SmallVector<VarDecl *, 4> BlockVars;
for (BlockDecl::capture_iterator
I = block->capture_begin(), E = block->capture_end(); I != E; ++I) {
VarDecl *var = I->getVariable();
if (I->isByRef() &&
!isAlreadyChecked(var) &&
var->getType()->isObjCObjectPointerType() &&
isImplicitStrong(var->getType())) {
BlockVars.push_back(var);
}
}
for (unsigned i = 0, e = BlockVars.size(); i != e; ++i) {
VarDecl *var = BlockVars[i];
CheckedVars.insert(var);
BlockVarChecker checker(var);
bool onlyValueOfVarIsNeeded = checker.TraverseStmt(block->getBody());
if (onlyValueOfVarIsNeeded) {
BlocksAttr *attr = var->getAttr<BlocksAttr>();
if(!attr)
continue;
bool hasARCRuntime = !Pass.Ctx.getLangOptions().ObjCNoAutoRefCountRuntime;
SourceManager &SM = Pass.Ctx.getSourceManager();
Transaction Trans(Pass.TA);
Pass.TA.replaceText(SM.getInstantiationLoc(attr->getLocation()),
"__block",
hasARCRuntime ? "__weak" : "__unsafe_unretained");
}
}
return true;
}
private:
bool isAlreadyChecked(VarDecl *VD) {
return CheckedVars.count(VD);
}
bool isImplicitStrong(QualType ty) {
if (isa<AttributedType>(ty.getTypePtr()))
return false;
return ty.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong;
}
};
class BlockObjCVarRewriter : public RecursiveASTVisitor<BlockObjCVarRewriter> {
MigrationPass &Pass;
public:
BlockObjCVarRewriter(MigrationPass &pass) : Pass(pass) { }
bool TraverseBlockDecl(BlockDecl *block) {
RootBlockObjCVarRewriter(Pass).TraverseDecl(block);
return true;
}
};
} // anonymous namespace
static void rewriteBlockObjCVariable(MigrationPass &pass) {
BlockObjCVarRewriter trans(pass);
trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// removeZeroOutIvarsInDealloc
//===----------------------------------------------------------------------===//
namespace {
class ZeroOutInDeallocRemover :
public RecursiveASTVisitor<ZeroOutInDeallocRemover> {
typedef RecursiveASTVisitor<ZeroOutInDeallocRemover> base;
MigrationPass &Pass;
llvm::DenseMap<ObjCPropertyDecl*, ObjCPropertyImplDecl*> SynthesizedProperties;
ImplicitParamDecl *SelfD;
llvm::DenseSet<Expr *> Removables;
public:
ZeroOutInDeallocRemover(MigrationPass &pass) : Pass(pass), SelfD(0) { }
bool VisitObjCMessageExpr(ObjCMessageExpr *ME) {
ASTContext &Ctx = Pass.Ctx;
TransformActions &TA = Pass.TA;
if (ME->getReceiverKind() != ObjCMessageExpr::Instance)
return true;
Expr *receiver = ME->getInstanceReceiver();
if (!receiver)
return true;
DeclRefExpr *refE = dyn_cast<DeclRefExpr>(receiver->IgnoreParenCasts());
if (!refE || refE->getDecl() != SelfD)
return true;
bool BackedBySynthesizeSetter = false;
for (llvm::DenseMap<ObjCPropertyDecl*, ObjCPropertyImplDecl*>::iterator
P = SynthesizedProperties.begin(),
E = SynthesizedProperties.end(); P != E; ++P) {
ObjCPropertyDecl *PropDecl = P->first;
if (PropDecl->getSetterName() == ME->getSelector()) {
BackedBySynthesizeSetter = true;
break;
}
}
if (!BackedBySynthesizeSetter)
return true;
// Remove the setter message if RHS is null
Transaction Trans(TA);
Expr *RHS = ME->getArg(0);
bool RHSIsNull =
RHS->isNullPointerConstant(Ctx,
Expr::NPC_ValueDependentIsNull);
if (RHSIsNull && isRemovable(ME))
TA.removeStmt(ME);
return true;
}
bool VisitBinaryOperator(BinaryOperator *BOE) {
if (isZeroingPropIvar(BOE) && isRemovable(BOE)) {
Transaction Trans(Pass.TA);
Pass.TA.removeStmt(BOE);
}
return true;
}
bool TraverseObjCMethodDecl(ObjCMethodDecl *D) {
if (D->getMethodFamily() != OMF_dealloc)
return true;
if (!D->hasBody())
return true;
ObjCImplDecl *IMD = dyn_cast<ObjCImplDecl>(D->getDeclContext());
if (!IMD)
return true;
SelfD = D->getSelfDecl();
RemovablesCollector(Removables).TraverseStmt(D->getBody());
// For a 'dealloc' method use, find all property implementations in
// this class implementation.
for (ObjCImplDecl::propimpl_iterator
I = IMD->propimpl_begin(), EI = IMD->propimpl_end(); I != EI; ++I) {
ObjCPropertyImplDecl *PID = *I;
if (PID->getPropertyImplementation() ==
ObjCPropertyImplDecl::Synthesize) {
ObjCPropertyDecl *PD = PID->getPropertyDecl();
ObjCMethodDecl *setterM = PD->getSetterMethodDecl();
if (!(setterM && setterM->isDefined())) {
ObjCPropertyDecl::PropertyAttributeKind AttrKind =
PD->getPropertyAttributes();
if (AttrKind &
(ObjCPropertyDecl::OBJC_PR_retain |
ObjCPropertyDecl::OBJC_PR_copy |
ObjCPropertyDecl::OBJC_PR_strong))
SynthesizedProperties[PD] = PID;
}
}
}
// Now, remove all zeroing of ivars etc.
base::TraverseObjCMethodDecl(D);
// clear out for next method.
SynthesizedProperties.clear();
SelfD = 0;
Removables.clear();
return true;
}
bool TraverseFunctionDecl(FunctionDecl *D) { return true; }
bool TraverseBlockDecl(BlockDecl *block) { return true; }
bool TraverseBlockExpr(BlockExpr *block) { return true; }
private:
bool isRemovable(Expr *E) const {
return Removables.count(E);
}
bool isZeroingPropIvar(Expr *E) {
BinaryOperator *BOE = dyn_cast_or_null<BinaryOperator>(E);
if (!BOE) return false;
if (BOE->getOpcode() == BO_Comma)
return isZeroingPropIvar(BOE->getLHS()) &&
isZeroingPropIvar(BOE->getRHS());
if (BOE->getOpcode() != BO_Assign)
return false;
ASTContext &Ctx = Pass.Ctx;
Expr *LHS = BOE->getLHS();
if (ObjCIvarRefExpr *IV = dyn_cast<ObjCIvarRefExpr>(LHS)) {
ObjCIvarDecl *IVDecl = IV->getDecl();
if (!IVDecl->getType()->isObjCObjectPointerType())
return false;
bool IvarBacksPropertySynthesis = false;
for (llvm::DenseMap<ObjCPropertyDecl*, ObjCPropertyImplDecl*>::iterator
P = SynthesizedProperties.begin(),
E = SynthesizedProperties.end(); P != E; ++P) {
ObjCPropertyImplDecl *PropImpDecl = P->second;
if (PropImpDecl && PropImpDecl->getPropertyIvarDecl() == IVDecl) {
IvarBacksPropertySynthesis = true;
break;
}
}
if (!IvarBacksPropertySynthesis)
return false;
}
else if (ObjCPropertyRefExpr *PropRefExp = dyn_cast<ObjCPropertyRefExpr>(LHS)) {
// TODO: Using implicit property decl.
if (PropRefExp->isImplicitProperty())
return false;
if (ObjCPropertyDecl *PDecl = PropRefExp->getExplicitProperty()) {
if (!SynthesizedProperties.count(PDecl))
return false;
}
}
else
return false;
Expr *RHS = BOE->getRHS();
bool RHSIsNull = RHS->isNullPointerConstant(Ctx,
Expr::NPC_ValueDependentIsNull);
if (RHSIsNull)
return true;
return isZeroingPropIvar(RHS);
}
};
} // anonymous namespace
static void removeZeroOutIvarsInDealloc(MigrationPass &pass) {
ZeroOutInDeallocRemover trans(pass);
trans.TraverseDecl(pass.Ctx.getTranslationUnitDecl());
}
//===----------------------------------------------------------------------===//
// getAllTransformations.
//===----------------------------------------------------------------------===//
static void independentTransforms(MigrationPass &pass) {
rewriteAutoreleasePool(pass);
changeIvarsOfAssignProperties(pass);
removeRetainReleaseDealloc(pass);
rewriteUnusedDelegateInit(pass);
removeZeroOutIvarsInDealloc(pass);
makeAssignARCSafe(pass);
castNonObjCToObjC(pass);
rewriteBlockObjCVariable(pass);
rewriteAllocCopyWithZone(pass);
}
std::vector<TransformFn> arcmt::getAllTransformations() {
std::vector<TransformFn> transforms;
// This must come first since rewriteAutoreleasePool depends on -release
// calls being present to determine the @autorelease ending scope.
transforms.push_back(independentTransforms);
transforms.push_back(removeEmptyStatements);
transforms.push_back(removeDeallocMethod);
return transforms;
}